1. Field of the Invention
The present invention relates to a speaker apparatus equipped with a first speaker unit for reproducing a low frequency range, and a second speaker unit for reproducing a medium frequency range and/or a high frequency range, and more particularly to a speaker apparatus capable of positioning the second speaker unit apart from a cabinet with the first speaker unit installed thereto.
2. Description of Related Art
As the speaker apparatus, conventionally there has widely been used a speaker apparatus, in which a first speaker unit 1 for reproducing a low frequency range and a second speaker unit 2 for reproducing a medium frequency range to a high frequency range are housed in a cabinet 3 common thereto as shown in FIG. 12. In this speaker apparatus, the first and second speaker units 1 and 2 are in parallel installed to a baffle plate 4 constituting the front plate of the cabinet 3.
When the first and second speaker units 1 and 2 are thus installed through the baffle plate 4, a part of reproduced sound emitted from the first and second speaker units 1 and 2 is reflected by the baffle plate 4. The reflected wave reflected by the baffle plate 4 is superposed on reproduced sound emitted on the front side of the first and second speaker units 1 and 2, whereby the reflected wave interferes with this reproduced sound to deteriorate the sound pressure reproducing characteristics.
When the first and second speaker units 1 and 2 are installed to the baffle plate 4, the sound emitted from the first and second speaker units 1 and 2 forms a sound field which spreads in the front of the baffle plate 4 so that a good sound field having a three-dimensional spread cannot be obtained.
In addition, in the case of stereophonic sound reproduction, two cabinets consisting of a cabinet 3 for left channel sound and a cabinet 3 for right channel sound are required, and it is inconvenient to carry them.
As a speaker apparatus for preventing the deteriorated sound pressure frequency characteristics caused by installation of speaker units on a baffle plate, and realizing a sound field spreading in three-dimensional directions and reproduction of sound excellent in presence, and yet capable of stereophonic reproduction with a single speaker apparatus, there is Japanese Patent Laid-Open Application No. 7-107585 filed by the present applicant in Japan.
The speaker apparatus described in this official gazette is constructed so that a pair of speaker units for reproducing medium and high frequency ranges are caused to float in the air. More specifically, this speaker apparatus is obtained by connecting a pair of speaker units for reproducing middle and high frequency ranges to a substantially cylindrical, tightly closed cabinet in which a speaker unit for reproducing a low frequency range is housed, through a supporting arm with a small diameter. The sound emitted from a speaker unit supported so as to be caused to float in the air through the supporting arm in this way is emitted around the speaker unit without being affected by the baffle plate, thus forming a sound field excellent in presence, having a three-dimensional spread without deteriorating the sound pressure frequency characteristics.
The speaker apparatus described in the official gazette is constructed to be installed at a predetermined place for use, and therefore, two mid end high-range speaker units supported on the tip end portions of respective supporting arms are installed to the cabinet through an oscillating mechanism respectively so that the spacing between these speaker units can be widened or narrowed. The respective supporting arms and speaker units are always placed in a state in which they project from the cabinet. The center-to-center spacing between the two mid and high-range speaker units is about 300 mm when narrowed most, and is about 700 mm when widened most.
A speaker apparatus is provided which is used by connecting it to an acoustic apparatus such as a portable tape recorder and a CD player through a connect cord. This type of speaker apparatus is carried, for use, together with a portable acoustic apparatus to which this speaker apparatus is connected.
If the speaker apparatus described in the official gazette applies as a portable speaker apparatus, the speaker unit supported through the supporting arm so that it projects from the apparatus body, makes the occupied area of the apparatus itself larger, and it becomes inconvenient to carry it. Also, the speaker unit projected from the apparatus body is very likely to be easily damaged during carrying.
It is an object of the present invention to provide a speaker apparatus excellent in the portability, and in the presence, for realizing good sound pressure frequency characteristics.
It is another object of the present invention to provide a speaker apparatus capable of reliably protecting a speaker unit which projects from the cabinet to be used.